Age Calculator
Calculate exact age in years, months and days from a date of birth, plus total months, weeks, days, the next birthday and leap-day handling.
Defaults to today; change it to get the age on any other date.
Enter a date of birth to see the exact age.
What is Age Calculator?
Calculates how old someone is on a given date, as whole years, months and days. It also shows the age as total months, weeks, days and hours, the weekday of birth and when the next birthday is.
How to use Age Calculator
- Enter the Date of birth.
- Leave Age on date as today, or change it to get the age on another date (for example a deadline or an exam day).
- For someone born on 29 February, choose whether the birthday counts on February 28 or March 1 in common years.
- Read the exact age and the totals; click Copy to copy the result.
Example
Born 1990-07-15, age on 2026-03-10
35 years, 7 months, 23 days – 13,022 days in total – next birthday Jul 15, 2026, in 127 days, turning 36
When to use Age Calculator
Use it for forms, eligibility checks, anniversaries or curiosity. Legal age rules for leap-day births differ between countries, so choose the rule that applies to you; for the difference between two arbitrary dates, use the date difference calculator.
How Age Calculator works
Completed years are counted by checking whether the birthday has occurred in the target year. The remaining months and days are a calendar difference from the last birthday: whole months are counted first, then the leftover days. Dates are handled as calendar days in UTC, so time zones and DST cannot shift the result by a day. Total days is the exact number of days between the two dates; weeks and hours are derived from it.
Common Use Cases
- Checking age on a cut-off date for school or sports eligibility
- Filling in forms that ask for age in years and months
- Counting days until your next birthday
- Finding the weekday you were born on
FAQs
How are leap-day (29 February) birthdays handled?
In years without 29 February you choose whether the birthday falls on 28 February or 1 March; the age and the next birthday follow that rule.
Why can the months and days differ from other calculators?
Month lengths vary, so tools use slightly different conventions. This one counts whole months from the last birthday and then the remaining days (the same convention as Java Period or PHP DateTime::diff).
Is the time of birth considered?
No, the calculation uses dates only.